Sunroof '87 5k

I've got a '87 5kcstq (that's a mouth full any way you say it) and my
sunroof has lost its mind. It started when it was making a bad noise
when retracting. I found out that the arms that pull down and hold the
spring loaded flap we not engaging properly and actually pushing it up.
Does any one know exactly what would cause this? Any help would be
appreciated.
Britt